BACKGROUND Due to the increasing number of diagnosed nonpalpable breast cancer cases,wire localization has been commonly performed for surgical guidance to remove nonpalpable breast lesions.This report presents a rare...BACKGROUND Due to the increasing number of diagnosed nonpalpable breast cancer cases,wire localization has been commonly performed for surgical guidance to remove nonpalpable breast lesions.This report presents a rare case of localized wire migration to a subcutaneous lesion of the upper back in a breast cancer patient undergoing breast-conserving surgery.CASE SUMMARY A 48-year-old female was scheduled for breast-conserving surgery for left breast cancer.Ultrasonography guided wire localization was performed intraoperatively by surgeon to localize the nonpalpable breast cancer.After axilla sentinel lymph node biopsy,we realized that the wire was not visualized.The wire was not found in the operation field,including the breast and axilla.Breast-conserving surgery was performed after wire re-localization.Intraoperative chest posteroanterior view revealed that the wire was located on the level of midaxillary line.Two days after the operation,a serial simple X-ray revealed that the wire was located on the subcutaneous lesion of the back.The wire tip was palpable under the skin of the upper back,and the wire was removed under local anesthesia.CONCLUSION Hooked wire misplacement can lead to fatal complications.Surgeons must consider the possibility of wire migration during breast cancer surgery.展开更多
The effective utilisation of steel fibre reinforced concrete (SFRC) requires in-depth and detailed understanding of bonding mechanisms governing the tensile behaviour. In response to this demand, this study presents a...The effective utilisation of steel fibre reinforced concrete (SFRC) requires in-depth and detailed understanding of bonding mechanisms governing the tensile behaviour. In response to this demand, this study presents an empirical description of the axial force required to pull out a hooked end steel fibre from a cementitious matrix. It is based upon consistent experimental tests that show the force versus displacement plot is formed from a sequence of events in which partial and full debonding at the interface is followed by bending of the hook knee to raise the force to its maximum. A loss of peak force occurs with the reversed plasticity involved in a full straightening of the fibre that precedes the rapid sliding to its full removal under a falling force. The stages are assembled in the said order with a piecewise connection between linear segments and a curve of exponential decay. A power law can be introduced to describe the knee bending stage if preferred. The normalised co-ordinates were adopted for the simple mathematical discontinuous function of the full pull-out process. Normalising force and displacement for hooked fibre is based upon the maximum values found for straight fibre pull out. This would apply to an overall embedded length of unity and a unit peak force for a full debonding of straight fibre in similar materials. For hooked fibre the normalised co-ordinates given refer to the initiation and duration of each event to be tabulated at fractions of the embedded length with multiples of that force. Such predictions are seen to be in good agreement with average pull-out response curves.展开更多
SIX thousand kilometers!10,000 li! 3000 yearsold! The only man-madestructure that can be seenfrom the moon! The bricks alonewould build four Egyptian pyra-mids! Wide enough for fourhorses abreast! You are not aman unt...SIX thousand kilometers!10,000 li! 3000 yearsold! The only man-madestructure that can be seenfrom the moon! The bricks alonewould build four Egyptian pyra-mids! Wide enough for fourhorses abreast! You are not aman until you’ve been to theWall! We have all heard at leastone of these claims.展开更多
Combining different types of fibers inside a concrete mixture was revealed to improve the strength properties of cementitious matrices by monitoring crack initiation and propagation.The contribution of hybrid fibers n...Combining different types of fibers inside a concrete mixture was revealed to improve the strength properties of cementitious matrices by monitoring crack initiation and propagation.The contribution of hybrid fibers needs to be thoroughly investigated,considering various parameters such as fibers type and content.The present study aims to carry out some mechanical and microstructural characteristics of Waste Ceramic Optimal Concrete(WOC)reinforced by hybrid fibers.Reinforcement materials consist of three different fiber types:hook-ended steel fiber(HK),crimped steel fiber(CR)and polyvinyl alcohol(PVA)fibers and the effect of their addition on the waste ceramic composites’mechanical behaviour.Furthermore,a microstructural analysis was carried out to understand the waste ceramic matrix composition and its bonding to hybrid fibers.Results showed that the addition of hybrid fibers improved the strength characteristics of the ceramic waste composites.For instance,the existence of PVA-CR increased the tensile and flexural strength of the waste ceramic composite by 85.44%and 70.37%,respectively,with respect to the control sample(WOC).As well as hybrid fiber exhibits improved morphological properties as a result of increased pore filling with dense and compact structure,as well as increased C-H crystals and denser structure in pastes as a result of the incorporation of hybrid fibers into the concrete mix.The present experimental research shows the choice of using steel fiber with PVA as a reinforcement material.The idea of adding hybrid fiber is to prepare the economic,environmental,and technological concrete.Moreover,it offers a possibility for improving concrete’s durability,which is vital.Finally,it was concluded that steel fiber is more durable,and stiffer and provides adequate first crack strength and ultimate strength.In contrast,the PVA fiber is relatively flexible and improves the post-crack zone’s toughness and strain capacity.展开更多
China ramps up its efforts to safeguard juveniles from the Internet gaming addiction Just before this year’s national college entrance exam,or the gaokao,on June 7-8,a letter from a despairing mother of student made ...China ramps up its efforts to safeguard juveniles from the Internet gaming addiction Just before this year’s national college entrance exam,or the gaokao,on June 7-8,a letter from a despairing mother of student made a big splash on Weibo,a Chinese Twitter-like microblogging platform.The mother described how her son,who used to be an outstanding learner,failed the exam展开更多
Chinese psychologists outline criteria for Internet addiction Day after day you are glued to your computer screen.You cannot get enough of online games,net shop-ping or cyber surfing.Your social life dete-riorates,and...Chinese psychologists outline criteria for Internet addiction Day after day you are glued to your computer screen.You cannot get enough of online games,net shop-ping or cyber surfing.Your social life dete-riorates,and so does your health.Chancesare that you are addicted to the Internet and you need counseling.展开更多
文摘BACKGROUND Due to the increasing number of diagnosed nonpalpable breast cancer cases,wire localization has been commonly performed for surgical guidance to remove nonpalpable breast lesions.This report presents a rare case of localized wire migration to a subcutaneous lesion of the upper back in a breast cancer patient undergoing breast-conserving surgery.CASE SUMMARY A 48-year-old female was scheduled for breast-conserving surgery for left breast cancer.Ultrasonography guided wire localization was performed intraoperatively by surgeon to localize the nonpalpable breast cancer.After axilla sentinel lymph node biopsy,we realized that the wire was not visualized.The wire was not found in the operation field,including the breast and axilla.Breast-conserving surgery was performed after wire re-localization.Intraoperative chest posteroanterior view revealed that the wire was located on the level of midaxillary line.Two days after the operation,a serial simple X-ray revealed that the wire was located on the subcutaneous lesion of the back.The wire tip was palpable under the skin of the upper back,and the wire was removed under local anesthesia.CONCLUSION Hooked wire misplacement can lead to fatal complications.Surgeons must consider the possibility of wire migration during breast cancer surgery.
文摘The effective utilisation of steel fibre reinforced concrete (SFRC) requires in-depth and detailed understanding of bonding mechanisms governing the tensile behaviour. In response to this demand, this study presents an empirical description of the axial force required to pull out a hooked end steel fibre from a cementitious matrix. It is based upon consistent experimental tests that show the force versus displacement plot is formed from a sequence of events in which partial and full debonding at the interface is followed by bending of the hook knee to raise the force to its maximum. A loss of peak force occurs with the reversed plasticity involved in a full straightening of the fibre that precedes the rapid sliding to its full removal under a falling force. The stages are assembled in the said order with a piecewise connection between linear segments and a curve of exponential decay. A power law can be introduced to describe the knee bending stage if preferred. The normalised co-ordinates were adopted for the simple mathematical discontinuous function of the full pull-out process. Normalising force and displacement for hooked fibre is based upon the maximum values found for straight fibre pull out. This would apply to an overall embedded length of unity and a unit peak force for a full debonding of straight fibre in similar materials. For hooked fibre the normalised co-ordinates given refer to the initiation and duration of each event to be tabulated at fractions of the embedded length with multiples of that force. Such predictions are seen to be in good agreement with average pull-out response curves.
文摘SIX thousand kilometers!10,000 li! 3000 yearsold! The only man-madestructure that can be seenfrom the moon! The bricks alonewould build four Egyptian pyra-mids! Wide enough for fourhorses abreast! You are not aman until you’ve been to theWall! We have all heard at leastone of these claims.
文摘Combining different types of fibers inside a concrete mixture was revealed to improve the strength properties of cementitious matrices by monitoring crack initiation and propagation.The contribution of hybrid fibers needs to be thoroughly investigated,considering various parameters such as fibers type and content.The present study aims to carry out some mechanical and microstructural characteristics of Waste Ceramic Optimal Concrete(WOC)reinforced by hybrid fibers.Reinforcement materials consist of three different fiber types:hook-ended steel fiber(HK),crimped steel fiber(CR)and polyvinyl alcohol(PVA)fibers and the effect of their addition on the waste ceramic composites’mechanical behaviour.Furthermore,a microstructural analysis was carried out to understand the waste ceramic matrix composition and its bonding to hybrid fibers.Results showed that the addition of hybrid fibers improved the strength characteristics of the ceramic waste composites.For instance,the existence of PVA-CR increased the tensile and flexural strength of the waste ceramic composite by 85.44%and 70.37%,respectively,with respect to the control sample(WOC).As well as hybrid fiber exhibits improved morphological properties as a result of increased pore filling with dense and compact structure,as well as increased C-H crystals and denser structure in pastes as a result of the incorporation of hybrid fibers into the concrete mix.The present experimental research shows the choice of using steel fiber with PVA as a reinforcement material.The idea of adding hybrid fiber is to prepare the economic,environmental,and technological concrete.Moreover,it offers a possibility for improving concrete’s durability,which is vital.Finally,it was concluded that steel fiber is more durable,and stiffer and provides adequate first crack strength and ultimate strength.In contrast,the PVA fiber is relatively flexible and improves the post-crack zone’s toughness and strain capacity.
文摘China ramps up its efforts to safeguard juveniles from the Internet gaming addiction Just before this year’s national college entrance exam,or the gaokao,on June 7-8,a letter from a despairing mother of student made a big splash on Weibo,a Chinese Twitter-like microblogging platform.The mother described how her son,who used to be an outstanding learner,failed the exam
文摘Chinese psychologists outline criteria for Internet addiction Day after day you are glued to your computer screen.You cannot get enough of online games,net shop-ping or cyber surfing.Your social life dete-riorates,and so does your health.Chancesare that you are addicted to the Internet and you need counseling.
